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Photo of a gypsy moth caterpillar on a tree - Click to enlarge
For Immediate Release: July 20, 2011
Contact: Lynne Richmond
(609) 633-2954

(TRENTON) – New Jersey Secretary of Agriculture Douglas H. Fisher today announced gypsy moth caterpillars damaged 1,317 acres of trees in 68 municipalities in 17 counties this spring.  More than half the damage was heavy.

“While the gypsy moth population has remained relatively low, they are still a significant threat to trees and given the right conditions, could have a resurgence,” said Secretary Fisher.  “We need to remain vigilant in our surveillance and suppression efforts to protect these natural resources.”

The Department’s annual aerial defoliation survey showed that spray efforts in the Camden County towns of Waterford and Winslow Townships were successful, with no trees defoliated in Waterford and 5 acres of trees with leaf loss in Winslow.  The aerial spray program in May comprised 274 acres in the two municipalities.

Ocean County had the most acres damaged by gypsy moths, with 228 acres of mostly moderate damage in Barnegat, Berkley, Jackson and Stafford Townships.  Burlington County had the second highest amount of damage with 176 acres in Eastampton, Evesham, Moorestown, Pemberton, and Southampton Townships and Wrightstown Borough.  Middlesex County had the highest amount of severe damage with 117 acres in Bridgewater, Old Bridge and Piscataway Townships. 

The Departments of Agriculture and Environmental Protection collaborate on gypsy moth suppression in New Jersey, with the NJDA handling wooded residential areas and DEP handling state-forested lands. 

“We strongly support continued efforts to battle gypsy moths to ensure the health of our forests,” said State Forester Lynn Fleming.  “A healthy forest provides many environmental and recreational benefits, and a strong forest is better able to ward off other pest invaders and better withstand potential forest fires.”

An egg mass survey conducted last fall qualified Waterford, Winslow and Chesilhurst in Camden County for the spring aerial suppression program, but Chesilhurst opted out of the program. 

Last year, gypsy moth caterpillars damaged 3,813 acres of trees, while 91,890 acres were defoliated in 2009. 

The gypsy moth population reached its peak in 2008 with 339,240 acres defoliated before the population began to decrease in 2009 through a combination of regular life cycle drop-off, beneficial fungus activity and natural predator increases in combination with the Department’s aggressive spray program.

The Department of Agriculture will continue to closely monitor, survey and recommend treatments, where necessary, to control the spread of the gypsy moth in the future.  Towns that experienced tree defoliation this year will soon receive letters informing them that they can request the Department to conduct an egg mass survey this fall to determine if spraying is necessary in 2012 to control gypsy moth caterpillars.  To qualify, residential or recreational forests must have an average of more than 500 egg masses per acre, and be at least 50 acres in size to qualify for participation in the voluntary program.   

The Department’s gypsy moth suppression efforts are aimed at preventing the loss of trees and protecting both urban and rural forests, which are important wildlife habitats as well as filters for the air we breathe.  Since 2006, repeated defoliations by gypsy moth caterpillars led to the death of more than 30,000 acres of trees throughout the state.

Two to three consecutive years of significant defoliation (defined as 75 percent or more) can kill an otherwise healthy tree. However, any gypsy moth defoliation can make trees more susceptible to other damage that can lead to the death of the tree.   Oak trees are the preferred host for gypsy moths, but the caterpillars can be found feeding on almost any tree in the vicinity.

To access the detailed 2011 New Jersey Gypsy Moth Aerial Defoliation survey and for more information on New Jersey’s gypsy moth suppression program, visit: www.nj.gov/agriculture/divisions/pi/prog/gypsymoth.html.